反应详情

温度

120 °C

To a solution of 2,6-diethylphenol (3.80 g, 25.3 mmol) in acetic acid (30 mL) hexamethylenetetraamine (5.3 g, 37.9 mmol) is added and the mixture is heated to 120° C. A first fraction of the solvent is distilled off (Dean-Stark), then the mixture is refluxed for 3 h. The mixture is cooled to rt, diluted with water (100 mL) and extracted twice with EA (2×200 mL). The organic extracts are washed with sat. aq. NaHCO3, dried and the solvent is removed in vacuo. The crude product is purified by column chromatography eluting with DCM containing 2% of methanol to give 3,5-diethyl-4-hydroxybenzaldehyde (1.8 g) as colourless solid; 1H NMR (CDCl3): δ 9.85 (s, 1H), 7.57 (s, 2H), 5.32 (s, 1H), 2.69 (q, J=7.6 Hz, 2H), 1.30 (t, J=7.6 Hz, 3H).

1. distillationA first fraction of the solvent is distilled off (Dean-Stark)
2. temperaturethe mixture is refluxed for 3 h
3. temperatureThe mixture is cooled to rt
4. additiondiluted with water (100 mL)
5. extractionextracted twice with EA (2×200 mL)
6. washThe organic extracts are washed with sat. aq. NaHCO3
7. customdried
8. customthe solvent is removed in vacuo
9. customThe crude product is purified by column chromatography
10. washeluting with DCM containing 2% of methanol